Mentholated talcum powder



Patented Nov. 28, 1933 warren pis mrsis FITPAT'ENT goreicE 11,936,845.LMENTHOLATED T no MfPoWDER 1 Alfred J. LautmanmDetroityMich.

No..-Drawing. ApplicationJuly;t15, 1931 jiSerial' No.1551'g051 K'Claims.(Cl. 167-82) This invention relates to improvements in'toilet powdersand method ofimanufacturingthe same, :tandw-has for its principal"object tonproduce a anewcandimproved powder incorporating 'thererzivitlrin ainovelmanner one 501 more of the-volatile alcohols so as toproduce a powder having marked c cooling" and soothingrefleots,andin-:which said :Eefiectseare.maintained for'some time after use.

zaA further object aofitheinvention is to produce 11101 atttoiletrpowders ofisther. characterdescribed, in

rwhichitheazadvantageous properties'may =be 're- -.:.ta'ined=over arelativelyxlong-periocl of time when *dtepttin a suitablercontainer,*butrirrwhich'release i J :fobthe:sactiveuelements'is'spromot'ed by applying imeowder to theiskinJ Other'obje'cts-"of'the'in- :='vention wiillappear from'atime to ztimee as theiol-lowing 'descriptionwproceeds.

Menthol; thymol=:and- =simi1ar' normally solidalcohols'have-been widelyused in medicinal and toilet preparations forltheir cooling 1properties,

this being largely due, of course;-to"tlieir high vapor pressure, butheretofore it has-not been 'deemed prac-tical to' use suchingredientswina "toilet-powder; due tothe unstabilityi'of such 'relatively" drymixtures wherein the' hi hly-fv'olatile -ingredients rapidly I disappearand'the powder quickly 'loses' its strength "when keptincontainers of"commercialor ordinaryiormf Talcjthe basic 3 ingredientof most toiletpowders because of it's desirable smoothness and other-physicalcharacteristics, hasmefely stir-f ace contact" for the 're- *te'ntionor'adsorptiom of *hig'hlyyolatile ingredientssuch' as mentholand thymol.Solutions-or g-emulsions 'of'these lattersubstances sprayed uponorrubbed into the tale are soon-evaporated. Similar1y,"otherbasic'ingredients of toilet powders'such as'zinc stearate, are notcapable of retaining such alcohols.

Z140 In carrying outmy invention, I proyide a toilet powdenhaving asusual a base of talc, zinc stearateor thelike, but in addition I'providea certain amount of highly porous or'absorbent material;preferably.consisting of diatomaceous 5 earth,'otherwise known as kie'selguhr,which con- "sists of the minute 'frustules andfragrnents of diatoms, .orin other words, the silicious remains of micrcscopiclalga occurring inthe natural de posits, usually fossiliferous As is well known.

- 'the'diatoms consist of microscopic cellular structures, .sosmall'that the material is highly absorbentin its finest form; Thismaterial isrthor- 'oughly' impregnated with the solid alcohol, .in suchmanner that the latter enters into the cells v. 5 onporousstructurerof.the diatoms and is held apertures such as usuallyemployed in the. coverthreinso as to greatly-lessen its surface-contact withthe air. 7

Furthermore, I increasethe lastingieflect of the -,c,001i ng vvaporsbythezad-dition of certain? mentho1-esters, which hydrolize incontact'withmois-a 5 ture from the-skin.-and airgproducing additionalmenthol as well as theaoids of the esters, which acids: are neutralizedby. a; -,suitable:, agent added for that purpose.

Referring now.- more specifically to the-propor tions of theseveralingredients and the methods of: preparing-thei same which I-have! found to give most satisfactory results, asuggestedfiormula issubstantially as follows: I w

. The, ingredientsof paragraphsjlBliand TLC) i above. are. preferably..incorporated, as separate groups, beforemixine withlthe baseincluded inparagraph (A),,as w'il1hereinafterappear. v

One methodofimpregnating thediatomaceous "earth with e the [alcoholsnmentioned consists in vaporizing the, latter. and, applying thevvaporunder moderate heatiand pressure .to a batchof idiatomaceousiearthcontained in an autoclave or other enclosed container, rpreferably...provided .with. asuitable agitating device sothattheyapors; may .be thoroughly, incorporated in the, di-

1 atomaceoussearth without; contactwith theatmosphere. .The batch isthencooledwhile still inthe container. ,sothatnthe v,vapors. may enter thecellular structure of the diatoms, through capillarity andcondensatlon.I find mostsatisiactory results are obtained by limiting the rela- 'tiveproportions of diatomaceous earthiand .talc

toisubstantially theamounts su gestedinasmuch as larger amounts of,diatomaceous earthtreated has described have a tendency to. afiectthe.free running properties of the powder, andito produoe a tendency to cakeor clog the relatively .small of 'dispensing.cans, The proportionsof thesolid alcohols can be varied somewhat, dependin'gupon the strength.desired or preferenoefor character- .istic odorvjof the'differentalcohols. tThehdegree ofi'absorbentvpowders ofthediatomaceousearth is naturally the limit of the amounts of thealcohols that can be fully absorbed, and the excess amounts will have atendency to disappear from the mixture in a relatively short time.

The diatomaceous earth, being a natural product, may vary somewhat ineffectiveness as an absorbent, depending upon the specific type and sizeof the diatoms constituting the particular deposit employed, and themode of preliminary treatment. I find that a purified air-floated whiteproduct may be obtained through the pulverizing of the crudediatomaceous earth, which product being easily obtainable in commercialquantities, is highly desirable for the'purpose.

After the diatomaceous earth has been impregnated as above described, it.is intimately mixed with the base materials including talc, zincstearate and borax, by the usual mechanical processes known to the art.

The menthol esters included in paragraph (C) -of the'suggested'formulaabove are of similar characteristics and may be used either separatelyor together. They are preferably added to the base independently of theimpregnating process of the diatomaceous earth as above described,

since such process has a tendency to break down v the esters. As apreferred method of application, the esters are dissolved in ethylalcohol and applied in the form of a solution or spray at atmospherictemperatures to the base and the impregnated diatomaceous earth, andcombined, if

' desired, with a suitable perfume such as the lilac suggested. As analternative method of application, the esters may be finely divided, andmixed directly with the base and impregnated diatomaceous earth.

Amongother absorbent or semi-absorbent materials which most nearlyapproach the properties of diatomaceous earth for the purpose of myinvention, may be mentioned pumice, asbestos,

or chalk, the latter made up .of microscopic shells of calciumcarbonate.

The talc may be replaced by zinc stearate as the principal base, or thelatter may be varied in proportions desirable for its well knownantiseptic and adhering properties. The borax is added as a neutralizingagent for the. menthol esters, as will hereinafter more fully appear.Other neutralizing agents may be used, as for instance calcium carbonatein the form of chalk.

As a modification of the process of manufacture above described, thediatomaceous earth may be mixed with the base before it is impregnatedby the solid alcohol. but in general be found that such process involvesthe handling of much greater bulk of material and an unnecessaryincrease in amount of the alcohols used, some of which is taken up bythe base by surface contact only, and is likely to escape from themixture by volatilization during the preparation or before the powder isput to use.

air, and especially the perspiration of the skin.

mild acet c or propionate acids resulting from such hydrolysis areneutralized and rendered innocuous by the borax or similar neutralizingagent employed. Such agent as a secondary function, also serves toneutralize any acids of the perspiration.

A further advantage, which is even more important from the commercialstandpoint, is the lasting effects of the essential properties of thealcohol ingredients such as menthol and thymol, whereby the productmaintains its strength and cooling effects for relatively long periodsof time, when kept in containers of commercial form. In fact, thesecondary cooling effect from hydrolysis of the esters may be maintainedindefinitely, while the initial effect from the absorbed alcohols iseasily retained as long as a can of average size lasts, when ordinarycaution is observed in keeping the can or container closed when not inuse.

As a further advantage of my improved powder, the diatomaceous earthcontent has a marked property of removing the objectionable shine" notedwith ordinary talcum powders, this property of the diatomaceous earthbeing due partly to its physical characteristics as distinguished fromthe flaky; shining crystals of talc, and partly to its absorptivepowers, by which it takes up excessive perspiration from the skin as thementhol and thymol become released therefrom by volatilization.

Although I have describedcertain preferred formula and modificationsthereof, and certain processes of manufacturing my improved toiletpowder, it will beunderstood that I do not wishto be limited to thespecific formulae described, but that similar properties may be obtainedby other compositions, either by change in propor- 'tions or bysubstitution of well known equivalents, '-and that other modifiedprocesses of manufacturemay be used, without departing from the spiritand scope of my invention. I do not, therefore, wish to be understood aslimiting myself to the ingredients, proportions or processes hereindisclosed, excepting as specifically defined in the' appended claims. 7r

Iclaim:

.;1. -In a toilet powder, a talc base, and diatomaceousearth having anormally solid alcohol of cooling properties impregnated within thecel--- lular structures of said diatomaceous earth, said diatomaceousearth being present in quantities of not exceeding five parts by weightto one hundred and twenty-five parts of said base.

2. The method of preparing a toilet powder ineluding diatomaceous earthand a normally solid volatile alcohol,-which includes steps of mixing abatch of the diatomaceous earth with the solid alcohol and applying heatand pressure sufficient to vaporize the latter and promote impregnationof the cellular structures of said diatomaceous earth by said vaporizedalcohol, and then cooling the mixture so as to condense the alcoholwithin said cellular structures and thereby retard evaporation thereofat normal temperatures.

3. The method of preparing a toilet power including diatomaceous earth,a relatively non-absorbent base, anda normally solid volatile alcoholwhich includes the steps of mixing a batch of the diatomaceous earthwith the solid alcohol under heat and pressure sufficient to vaporizethe latter and promote impregnation of the cellular structures of thediatomaceousearth by said vaporized alcohol, then cooling the mixture soas to condense the alcohol within said cellular structures and therebyretard evaporation thereof at normal temperatures, and thereafter mixingsaid impregnated diatomaceous earth with said base.

ALFRED J. LAUTMANN.

